Categories in MarginEdge (ME) are associated with products, so any changes must be made by finding the product and using the Edit Product page. If you aren't sure how to find the product, see below for help on ways to find products.
Once on the Edit Product page, you can simply select a new category using the Category dropdown selector found beneath the product name. Click "Save", and that's it. From that point forward, any invoices that contain that product that isn't yet sent to accounting will be sent using the new category.
What if the "Edit Product" button is disabled?
If the "Edit Product" button is disabled, you'll need to have Restaurant Admin access added to your user account. Ask your current Restaurant Admin user for this change.
Can I restrict the categories for a specific vendor?
Yes! If you want to lock your linen vendor to only allow the category "Linen", or want to lock Office Depot to only allow "Office Supplies", or even want to lock a wine distributor to only "Wine", you can do this. To pick one category (or a select few) that will be allowed for a vendor, you can do this using Category Restrictions, described in this article on Advanced Vendor Configuration Options.
How can I find a specific product?
You can find a product in one of a few places. You can find it using the...
Go to the Products menu, and Products submenu and search for the product, click on the row for the product, and then click the "Edit Product" button to change its category.
Vendor Items page
Go to Vendors > Vendor Items page, and search by either vendor name or the item's name. Once you find the item, click the row. From there, you will see the Vendor Item details, including the Product it is associated with, and you can click the "Edit Product" button to change its category.
Go to the Vendors page (click on Vendors > Vendors), and select the appropriate vendor. On the Vendor Details page, you will see a tab listing all Vendor Items purchased from the vendor. You can select any Vendor Item by clicking its row, then you will see the Vendor Item details, including the Product it is associated with. Click the "Edit Product" button to change its category.
If there is a category you don't see, you also have the ability to add and edit your categories. For more information on that, check out this article on the topic.